Generally, there is known a water content detection sensor for detecting presence or generation of water content at a time when the water content or water adheres between electrodes, and then, electric current passes (for example, refer to Patent Literature 1, 2, 3). Such water content detection sensors are utilized for an excrement receiver, a diaper and so on, and when the water content adheres between the electrodes by the urination, for example, the electrodes are short-circuited and the urination is thereby detected.
Moreover, there is also known an urine-gathering system in which the urine is received by an excrement receiver or a saucer inserted in a diaper, and the urine received in the saucer is sucked by a vacuum pump every time when the urination is detected(for example, refer to Patent Literature 4).    Patent Literature 1: JP-63-290950    Patent Literature 2: JP-2000-19136    Patent Literature 3: JP-2002-82080    Patent Literature 4: JP-2004-267517